The P2573 code indicates that the vehicle's control module has detected that the signal from the direct ozone reduction catalyst deterioration sensor is outside the expected range or performance parameters. This sensor monitors the health and efficiency of the catalyst that reduces ozone in the exhaust.
The sensor itself may have failed or be providing inaccurate readings due to age, contamination, or internal malfunction.
Corroded, damaged, or loose connections in the sensor circuit can cause intermittent or out‑of‑range signals.
Leaks upstream of the sensor can introduce extra oxygen or temperature variations that affect the sensor's measurements.
Significant buildup of deposits or physical damage in the catalyst can reduce its ability to reduce ozone, leading the sensor to report a fault.
A rare PCM fault can misinterpret sensor data, but this is usually considered only after sensor and wiring checks.
Replacing the PCM is seldom necessary; the code is most often caused by a faulty sensor, wiring issue, or exhaust leak, which should be diagnosed first.
Yes, if the catalyst has deteriorated to the point where it no longer meets the ozone reduction target, the sensor may report a performance fault.
It is primarily an emissions‑control monitoring code; it usually does not affect drivability directly, though it can cause a failed emissions test.
Yes, after fixing the underlying issue, use a scan tool to clear the code and verify that it does not return.